Is clutch size limited by incubation ability in northern lapwings?

Abstract

Summary1. The incubation-limitation hypothesis states that clutch size in shorebirds is constrained by the ability to incubate more than four eggs successfully. In order to test predictions from this hypothesis, clutches of northern lapwings ( Vanellus vanellus ) were here experimentally increased and reduced by one egg at the onset of incubation. Parental behaviour, incubation time, hatching synchrony, egg viability, hatching success and body condition of hatchlings was compared with unmanipulated clutches. 2. Nest desertion and egg breakage was not observed in any of the experimental nests, showing that clutch enlargement did not alter the parental behaviour adversely. 3. There were no differences among the experimental groups in male and female attentiveness, but the total nest attentiveness was lower in reduced clutches than in the other clutch sizes; nor did the parents' frequency of nest visits differ between clutch sizes. 4. Enlarged clutches were incubated longer than controls and reduced clutches. There were, however, no significant differences among clutch sizes in partial or total clutch predation rates. Hatchability of the eggs (proportion of eggs hatching of those present in nests at the end of incubation) was marginally lower in the enlarged clutches (92·5% vs. 100% in the two other groups). 5. Contrary to predicted, hatching success was highest in enlarged clutches. The numbers of hatched eggs calculated from Mayfield estimates of daily nest and egg survival rates were 0·93, 2·10 and 3·14 in three-, four-and five-egg clutches, respectively. 6. When controlling for egg volume, mean body mass of newly hatched chicks was lower in clutches with five eggs than in other nests. 7. We suggest that the lowered body condition of chicks could outweigh the benefits of laying five instead of four eggs in northern lapwings. Future studies of the selective mechanisms of clutch size in shorebirds should not only focus on the number of young that hatch, but also their quality.

Avian Incubation Patterns Reflect Temporal Changes in Developing Clutches

“…Brooding conditions affect avian embryo growth, survival, hatchling weight, and subsequent offspring behavior and fecundity [1] [2] [3] [4]. The type of parental care of eggs, and the subsequent degree of parental influence on pre-hatch conditions, varies greatly among species [5].…”

Experimental heating reveals nest temperature affects nestling condition in tree swallows ( Tachycineta bicolor )

“…We predicted that nestlings heated as embryos during incubation would have higher body condition (i.e. residual mass) than control nestlings due to greater retention of energy reserves, as previous work has suggested that suboptimal developmental conditions lead to reduced body condition (Larsen et al 2003), though increased temperatures can lead to increased water loss and lower mass at hatching (Reid et al 2000a). …”

Limited male incubation ability and the evolution of egg size in shorebirds

“…However, reduced incubation ability may also negatively influence the performance of bird embryos in more subtle ways. In northern lapwings (Vanellus vanellus), newly hatched chicks from experimentally enlarged clutches were in poorer body condition than controls, perhaps increasing their risk of mortality (Larsen et al 2003). Further, prenatal developmental conditions can have longterm effects on zebra finch (Taeniopygia guttata) reproductive performance later in life, without producing a clear effect on growth and development (Gorman & Nager 2004).…”